diff --git a/dd-trace-core/src/main/java/datadog/trace/core/CoreSpan.java b/dd-trace-core/src/main/java/datadog/trace/core/CoreSpan.java
index a6ced35967c..4d0d8c87f99 100644
--- a/dd-trace-core/src/main/java/datadog/trace/core/CoreSpan.java
+++ b/dd-trace-core/src/main/java/datadog/trace/core/CoreSpan.java
@@ -1,7 +1,6 @@
 package datadog.trace.core;
 
 import datadog.trace.api.DDTraceId;
-import datadog.trace.bootstrap.instrumentation.api.Tags;
 import java.util.Map;
 
 public interface CoreSpan<T extends CoreSpan<T>> {
@@ -10,9 +9,7 @@ public interface CoreSpan<T extends CoreSpan<T>> {
 
   String getServiceName();
 
-  default CharSequence getServiceNameSource() {
-    return null;
-  }
+  CharSequence getServiceNameSource();
 
   CharSequence getOperationName();
 
@@ -62,13 +59,9 @@ default CharSequence getServiceNameSource() {
 
   <U> U getTag(CharSequence name);
 
-  default <U> U unsafeGetTag(CharSequence name, U defaultValue) {
-    return getTag(name, defaultValue);
-  }
+  <U> U unsafeGetTag(CharSequence name, U defaultValue);
 
-  default <U> U unsafeGetTag(CharSequence name) {
-    return getTag(name);
-  }
+  <U> U unsafeGetTag(CharSequence name);
 
   boolean hasSamplingPriority();
 
@@ -81,10 +74,7 @@ default <U> U unsafeGetTag(CharSequence name) {
 
   boolean isForceKeep();
 
-  default boolean isKind(SpanKindFilter filter) {
-    Object kind = unsafeGetTag(Tags.SPAN_KIND);
-    return filter.matches(kind == null ? null : kind.toString());
-  }
+  boolean isKind(SpanKindFilter filter);
 
   CharSequence getType();
 
diff --git a/dd-trace-core/src/test/groovy/datadog/trace/common/metrics/SimpleSpan.groovy b/dd-trace-core/src/test/groovy/datadog/trace/common/metrics/SimpleSpan.groovy
index 2fd8554d499..f23045856ef 100644
--- a/dd-trace-core/src/test/groovy/datadog/trace/common/metrics/SimpleSpan.groovy
+++ b/dd-trace-core/src/test/groovy/datadog/trace/common/metrics/SimpleSpan.groovy
@@ -199,6 +199,16 @@ class SimpleSpan implements CoreSpan<SimpleSpan> {
     return getTag(name, null)
   }
 
+  @Override
+  <U> U unsafeGetTag(CharSequence name, U defaultValue) {
+    return getTag(name, defaultValue)
+  }
+
+  @Override
+  <U> U unsafeGetTag(CharSequence name) {
+    return getTag(name)
+  }
+
   @Override
   boolean hasSamplingPriority() {
     return false
diff --git a/dd-trace-core/src/test/java/datadog/trace/common/writer/TraceGenerator.java b/dd-trace-core/src/test/java/datadog/trace/common/writer/TraceGenerator.java
index 618b2ef77ae..00610ddbb61 100644
--- a/dd-trace-core/src/test/java/datadog/trace/common/writer/TraceGenerator.java
+++ b/dd-trace-core/src/test/java/datadog/trace/common/writer/TraceGenerator.java
@@ -11,10 +11,12 @@
 import datadog.trace.api.TagMap;
 import datadog.trace.api.sampling.PrioritySampling;
 import datadog.trace.bootstrap.instrumentation.api.AgentSpanLink;
+import datadog.trace.bootstrap.instrumentation.api.Tags;
 import datadog.trace.bootstrap.instrumentation.api.UTF8BytesString;
 import datadog.trace.core.CoreSpan;
 import datadog.trace.core.Metadata;
 import datadog.trace.core.MetadataConsumer;
+import datadog.trace.core.SpanKindFilter;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.util.ArrayList;
@@ -502,5 +504,26 @@ public PojoSpan setMetaStruct(String field, Object value) {
     public int getLongRunningVersion() {
       return 0;
     }
+
+    @Override
+    public CharSequence getServiceNameSource() {
+      return null;
+    }
+
+    @Override
+    public boolean isKind(SpanKindFilter filter) {
+      Object kind = unsafeGetTag(Tags.SPAN_KIND);
+      return filter.matches(kind == null ? null : kind.toString());
+    }
+
+    @Override
+    public <U> U unsafeGetTag(CharSequence name, U defaultValue) {
+      return getTag(name, defaultValue);
+    }
+
+    @Override
+    public <U> U unsafeGetTag(CharSequence name) {
+      return getTag(name);
+    }
   }
 }
diff --git a/dd-trace-core/src/traceAgentTest/groovy/TraceGenerator.groovy b/dd-trace-core/src/traceAgentTest/groovy/TraceGenerator.groovy
index e668d0112a6..8477ad00df3 100644
--- a/dd-trace-core/src/traceAgentTest/groovy/TraceGenerator.groovy
+++ b/dd-trace-core/src/traceAgentTest/groovy/TraceGenerator.groovy
@@ -1,6 +1,7 @@
 import static datadog.trace.api.ProcessTags.tagsForSerialization
 import static datadog.trace.api.TagMap.fromMap
 import static datadog.trace.api.sampling.PrioritySampling.UNSET
+import static datadog.trace.bootstrap.instrumentation.api.Tags.SPAN_KIND
 import static java.lang.Thread.currentThread
 import static java.util.Collections.emptyList
 
@@ -13,6 +14,7 @@ import datadog.trace.bootstrap.instrumentation.api.UTF8BytesString
 import datadog.trace.core.CoreSpan
 import datadog.trace.core.Metadata
 import datadog.trace.core.MetadataConsumer
+import datadog.trace.core.SpanKindFilter
 import java.util.concurrent.ThreadLocalRandom
 import java.util.concurrent.TimeUnit
 
@@ -173,6 +175,11 @@ class TraceGenerator {
       return serviceName
     }
 
+    @Override
+    CharSequence getServiceNameSource() {
+      return null
+    }
+
     @Override
     CharSequence getOperationName() {
       return operationName
@@ -298,6 +305,12 @@ class TraceGenerator {
       return false
     }
 
+    @Override
+    boolean isKind(SpanKindFilter filter) {
+      Object kind = unsafeGetTag(SPAN_KIND)
+      return filter.matches(kind == null ? null : kind.toString())
+    }
+
     Map<String, String> getBaggage() {
       return metadata.getBaggage()
     }
@@ -394,6 +407,16 @@ class TraceGenerator {
       return value as U
     }
 
+    @Override
+    <U> U unsafeGetTag(CharSequence name, U defaultValue) {
+      return getTag(name, defaultValue)
+    }
+
+    @Override
+    <U> U unsafeGetTag(CharSequence name) {
+      return getTag(name)
+    }
+
     @Override
     boolean hasSamplingPriority() {
       return false